:root {
    --primary:      #1a56db;
    --primary-dark: #1241a8;
    --bg:           #f0f4f8;
    --text:         #1e293b;
    --muted:        #64748b;
    --border:       #d1d9e6;
    --success:      #16a34a;
    --success-light:#dcfce7;
  }

  * { box-sizing: border-box; }

  body {
    font-family: 'Noto Sans JP', sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
  }

  /* ── 背景装飾 ── */
  .bg-deco {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
  }
  .bg-deco::before {
    content: '';
    position: absolute;
    top: -120px; right: -120px;
    width: 480px; height: 480px;
    background: radial-gradient(circle, rgba(26,86,219,.08) 0%, transparent 70%);
    border-radius: 50%;
  }
  .bg-deco::after {
    content: '';
    position: absolute;
    bottom: -80px; left: -80px;
    width: 360px; height: 360px;
    background: radial-gradient(circle, rgba(22,163,74,.06) 0%, transparent 70%);
    border-radius: 50%;
  }

  /* ── メインコンテンツ ── */
  main {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px 16px;
    position: relative;
    z-index: 1;
  }

  /* ── カード ── */
  .thanks-card {
    background: #fff;
    border-radius: 6px;
    box-shadow: 0 12px 40px rgba(30,41,59,.10);
    padding: 56px 48px 48px;
    max-width: 720px;
    width: 100%;
    text-align: center;
    animation: fadeUp .6s ease both;
  }

  @keyframes fadeUp {
    from { opacity: 0; transform: translateY(24px); }
    to   { opacity: 1; transform: translateY(0); }
  }

  /* ── チェックアイコン ── */
  .check-circle {
    width: 88px; height: 88px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--success-light), #bbf7d0);
    display: flex; align-items: center; justify-content: center;
    margin: 0 auto 28px;
    animation: popIn .5s .3s cubic-bezier(.34,1.56,.64,1) both;
  }
  @keyframes popIn {
    from { opacity: 0; transform: scale(.5); }
    to   { opacity: 1; transform: scale(1); }
  }
  .check-circle i {
    font-size: 2.6rem;
    color: var(--success);
  }

  /* ── ラベル ── */
  .thanks-label {
    font-size: .72rem;
    font-weight: 700;
    letter-spacing: .18em;
    color: var(--success);
    text-transform: uppercase;
    margin-bottom: 8px;
    display: block;
  }

  /* ── タイトル ── */
  .thanks-title {
    font-size: 1.55rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 20px;
    line-height: 1.4;
  }

  /* ── 区切り ── */
  .thanks-divider {
    width: 48px; height: 3px;
    background: linear-gradient(90deg, var(--primary), #60a5fa);
    border-radius: 2px;
    margin: 0 auto 24px;
  }

  /* ── 本文 ── */
  .thanks-body {
    font-size: .92rem;
    color: var(--muted);
    line-height: 1.9;
    margin-bottom: 32px;
  }
  .thanks-body strong {
    color: var(--text);
    font-weight: 600;
  }

  /* ── インフォボックス ── */
  .info-box {
    background: #f8faff;
    border: 1.5px solid #dbeafe;
    border-radius: 4px;
    padding: 18px 22px;
    margin-bottom: 36px;
    text-align: left;
  }
  .info-box .info-row {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    font-size: .86rem;
    color: var(--muted);
    padding: 6px 0;
  }
  .info-box .info-row + .info-row {
    border-top: 1px solid #e8eef8;
  }
  .info-box .info-row i {
    color: var(--primary);
    width: 16px;
    flex-shrink: 0;
    margin-top: 2px;
  }

  /* ── ボタン群 ── */
  .btn-group-thanks {
    display: flex;
    flex-direction: column;
    gap: 12px;
    align-items: center;
  }
  .btn-top-page {
    background: linear-gradient(135deg, #0d6efd 0%, #0d6efda8 100%);
    color: #fff;
    border: none;
    border-radius: 10px;
    padding: 13px 42px;
    font-size: .95rem;
    font-weight: 600;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    box-shadow: 0 4px 16px rgba(26,86,219,.30);
    transition: opacity .2s, transform .15s;
    letter-spacing: .02em;
  }
  .btn-top-page:hover {
    opacity: .88;
    color: #fff;
    transform: translateY(-1px);
  }
  .btn-close-note {
    font-size: .82rem;
    color: var(--muted);
  }

  /* ── フッター ──
  footer {
    text-align: center;
    padding: 20px 0;
    font-size: .78rem;
    color: #94a3b8;
    position: relative;
    z-index: 1;
  }
 */
  /* ── ステッパー（進捗表示）── */
  .stepper {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0;
    margin-bottom: 36px;
  }
  .step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
  }
  .step-circle {
    width: 28px; height: 28px;
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: .72rem;
    font-weight: 700;
  }
  .step-done .step-circle {
    background: var(--success);
    color: #fff;
  }
  .step-label {
    font-size: .65rem;
    color: var(--muted);
    white-space: nowrap;
  }
  .step-done .step-label { color: var(--success); font-weight: 600; }
  .step-line {
    width: 48px; height: 2px;
    background: var(--success);
    margin-bottom: 16px;
  }

  /* ── レスポンシブ ── */
  @media (max-width: 520px) {
    .thanks-card { padding: 36px 22px 36px; border-radius: 16px; }
    .thanks-title { font-size: 1.25rem; }
    .info-box { padding: 14px 16px; }
    .btn-top-page { padding: 12px 28px; width: 100%; justify-content: center; }
    .step-line { width: 28px; }
  }